Multi-Input Multi-Output Radio Communications

The use of multi-element antenna arrays in wireless radio-frequency
links promises an enormous increase in throughput. Theoretical results
indicate that a link using N transmitting and N receiving
antennas can achieve an information-theoretic capacity as high as N
times that of a single-input, single-output link. Our research has addressed
several issues through analysis and simulation. We have quantified the impact
of spatially correlated fading on link capacity, and have studied various
strategies for allocation of power among transmitting elements in the
presence of this fading correlation. We have studied layered space-time codes,
which can achieve bit rates close to capacity, while maintaining manageable
decoding complexity. In particular, we have analyzed the performance of
layered space-time codes in slow and fast fading environments, and have proposed a
set of design criteria for these codes.